Experimental study on the flexural behavior of a prefabricated #br# large-cantilevered prestressed UHPC thin-walled bent cap
Li Lifeng1,2 Ye Meng1 Hu Fangjian3 Liao Rui3 Tang Jinliang1 Shao Xudong1,2
1. College of Civil Engineering, Hunan University, Changsha 410082, China; 2. Key Laboratory for Wind and Bridge
Engineering of Hunan Province, Hunan University, Changsha 410082, China;
3. Shanghai Urban Construction Design & Research Institute, Shanghai 200125, China
Abstract： In order to reduce the excessive self-weight and solve the difficulty of precast and assembly for conventional concrete bent caps, a fully prefabricated lightweight prestressed ultra-high performance concrete(UHPC) large-cantilevered thin-walled bent cap was proposed. The self-weight can be reduced by about 40%.A 1∶2 scaled bent cap was designed and tested to investigate the crack resistance and the flexural behavior. Some parameters, such as deformation, strain, crack distribution, cracking and failure load were obtained. Based on the test results, the strain hardening characteristic of UHPC, French UHPC code and Swiss UHPC code, the calculation methods for cracking and the ultimate bending moment were investigated. Meanwhile, the concrete damage plasticity(CDP) model in ABAQUS was used to simulate the loading process of the UHPC bent cap. It is concluded that the new UHPC bent cap possesses excellent deformation capacity and anti-cracking behavior with fine and closely spaced cracks. The cracking and ultimate bending moment obtained by the proposed calculation method are in good agreement with the test results. It is recommended that the plastic influence coefficient be 1.0 and 2.0 respectively to calculate the initial cracking moment. The flexural behavior and placing space can be effectively improved by increasing the prestressing tendons and decreasing the reinforcements properly. The research results can provide reference for the design and application of the UHPC bent cap.
李立峰 叶萌 胡方健 廖瑞 唐金良 邵旭东 . 预制大悬臂预应力UHPC薄壁盖梁#br# 抗弯性能的试验研究[J]. 土木工程学报, 2020, 53(2): 92-104.
Li Lifeng Ye Meng Hu Fangjian Liao Rui Tang Jinliang Shao Xudong. Experimental study on the flexural behavior of a prefabricated #br# large-cantilevered prestressed UHPC thin-walled bent cap. 土木工程学报, 2020, 53(2): 92-104.
